DE 10 2008 013 365 A1 describes a lateral butt joint between two adjacent fuselage sections. The lateral butt joint is formed between the two adjacent fuselage sections, which in each case are sheeted with an outer skin, whose end regions comprise wedge-shaped thickened parts whose inclinations point in opposite directions. Special wedges interact with the aforesaid so as to cause tolerance compensation in radial and axial directions of the fuselage section. In this arrangement a lateral butt-joint plate, which forms part of the frame element profile, comes to rest against the top of the wedges allocated at this position.
Furthermore, the frame element profile comprises a trapezoidal recess, through which two pieces of stringer couplings are inserted so as to be arranged side by side, in order to ensure the connection of stringers that are aligned coaxially relative to each other. In this arrangement each stringer is associated with a fuselage section and ends in front of the peripheral region of the fuselage section at the position in which the lateral butt-joint plate including the wedge is placed. Thus the stringer couplings are used to bridge the frame element profile in order to ensure continuous extension of the stringer in longitudinal direction of the fuselage. Apart from its stiffening function the frame element profile also fulfils a connection function in relation to the adjacent fuselage sections strung together, which fuselage sections are normally riveted by way of said frame element profile. Likewise, the stringer couplings, in a sandwich construction, are riveted to the end regions of the associated stringers and to the outer skin, and in the region of the frame element profile are also riveted to the aforesaid and to the wedges and finally to the outer skin. Apart from this, it has been proposed that the connections be made by means of screws or at least partly by bonding or welding. In this arrangement the selected type of connection essentially depends on the selection of the materials or the components and on the stability requirements.
In the aforementioned patent specification, preferably aluminum alloys, titanium alloys, stainless steel alloys or fiber composite materials, for example carbon-fiber-reinforced epoxy resins or thermoplastic materials, in particular polyetheretherketone (PEEK), are proposed as materials for the outer skin, the frame element profile, the stringers, and the stringer couplings.
Because of the stringent requirements relating to the quality of the connections and the many components that are to be interconnected in a sandwich-like manner, assembly of the stringer couplings in the above-described intersection region between the stringers and the frame elements of a fuselage is quite elaborate and expensive.
From DE 10 2008 010 197 A1 a similar lateral butt joint is described as is an associated method for the assembly of two fuselage sections while creating a butt joint. In this document the fuselage skin comprises a fiber-reinforced plastic material, in particular wound fuselage sections for a commercial aircraft. To make it possible to join these special fuselage sections it is proposed that the fuselage sections to be joined first be positioned against each other. Subsequently, at least one lateral butt-joint plate comprising a fiber-reinforced thermoplastic material is heated and adjusted in such a manner that tolerance compensation between the first and second deviating cross-sectional geometric shapes of the two fuselage sections is made possible. As an alternative, at least one end region of a second fuselage section comprising a fiber-reinforced thermoplastic material can be heated, after which the two fuselage sections are joined. Finally, here again, preferably riveting of the components that are to be joined in a sandwich-like manner takes place, which components comprise the outer skin, the special lateral butt-joint plate, the end regions of the stringers of each fuselage section, which stringers are aligned coaxially relative to each other, and the stringer coupling which bridges and connects the two. Furthermore, it is proposed that the stringer coupling also be heated prior to assembly, for the purpose of tolerance compensation, and for it to be adjusted to the course of the adjacent components. In this arrangement, too, for each connecting position preferably two stringer couplings are used, each with an L-shaped cross section, in conjunction with stringers that are T-shaped in cross section. Moreover, the end regions of the abutting fuselage sections are also interconnected by way of the lateral butt-joint plate, preferably in a riveting process.
In practical application, riveting the stringer couplings to the outer skin and to the lateral butt-joint plate is carried out in several process steps. In this arrangement pilot holes are first made from the outside through the outer skin. Subsequently the already pre-installed stringer coupling is deinstalled, cleaned, deburred and a sealing compound is applied to it before said component is then reinstalled with the use of temporary auxiliary connection elements. In the next process step the holes are sequentially drilled to final dimension and are riveted with a precise fit. This installation method ensures that no drilling swarf reaches its way between the components to be interconnected, but said installation method is quite time-consuming.